Double motor vacuum

ABSTRACT

A vacuum having a series of motors and fans. As the fans rotate, they draw air into the vacuum. The volume of the air brought into the vacuum is maximized by positioning the fans in series. A plurality of fans is positioned so that outflow from a first fan is the primary inflow into a second fan, and so forth. Together the fans will draw more air than one could alone. By positioning the fans in series, the external diameter of the vacuum does not need to be any larger than it would for a vacuum having a single fan. The fans and motors are contained in a housing having an intake aperture. The intake aperture is preferably separated from the intake opening to the first fan and is preferably slightly smaller than the intake openings to the first fan. This will cause air entering the housing to accelerate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to vacuum motors in general and in particular tohigh efficiency high strength vacuum motors.

2. Prior Art

Electric motors are commonly used to drive the fans in vacuums. The moreair the fan entrains, the stronger the vacuum will be. Typically,greater suction strength is obtained by providing the vacuums with morepowerful motors which are capable of rotating the fans at a higher rate.However, strengthening the vacuum output in this manner creates severalproblems. First, more powerful motors require more amperage. Where thevacuum is battery operated, these more powerful motors will exhaust thebattery more quickly, resulting in a shorter operating life for thevacuum.

Another problem with increasing vacuum strength by simply using astronger motor is that stronger motors are generally larger than theirstandard counterparts. Thus, increasing motor strength will generallyrequire the size of the vacuum housing to be increased as well. This canbe undesirable, particularly in hand held vacuums. Smaller more compactvacuums are often desired in many of the environments where hand heldvacuums are used and stored, such as in automobiles, office work spaces,and the like. Anything that increases the girth of these vacuums isoften unwanted.

Fan size may also be increased to increase the strength of the vacuum.However, increasing fan size will increase the load on the motor andrequire the size of the housing to increase as well. As with increasingmotor power, the increased load on the motor will more rapidly depletebattery life when cordless vacuums are employed.

The volume of air moving through the vacuum will be controlled by thefan size and speed of rotation. However, the speed of the air enteringthe vacuum may also be controlled by the size and shape of the airinlet. The strength of the vacuum may be enhanced by accelerating theair as it enters the vacuum. Accordingly, a vacuum meeting the followingobjectives is desired.

OBJECTS OF THE INVENTION

It is an object of the invention to provide a vacuum of increasedstrength.

It another object of the invention to provide a vacuum of increasedstrength without increasing the girth of the vacuum housing.

It is yet another object of the invention to provide a vacuum ofincreased strength without increasing the size of the vacuum fan.

It is still another object of the invention to provide a vacuum ofincreased strength without increasing the size of the vacuum motor.

It is yet another object of the invention to provide a vacuum having animproved air inlet configuration.

SUMMARY OF THE INVENTION

The invention comprises a vacuum having a series of motors. Each motoris equipped with a fan. The motors are configured to drive the fans. Asthe fans rotate, they will draw air into the vacuum. The flow of airinto the vacuum will create the suction used to pick up dirt and otherparticles. The strength of the vacuum is determined by the volume of theair moving into the vacuum and the speed at which the air is moving.

In the present invention, the volume of air brought into the vacuum ismaximized by positioning the motors and their fans in series. Aplurality of motors is positioned so that the outflow from a first motoris the sole or primary inflow into a second motor and fan, and so forth.Together the fans will draw more air into the vacuum than one couldalone. By positioning the motors and fans in series, the girth orexternal diameter of the vacuum body does not need to be any larger thanit would for a conventional vacuum with a single motor and fan.

In the preferred embodiment, the fans and motors are provided with ahousing. The housing prevents the second motor and fan from taking inair from anywhere except the outflow of the first motor and fan.Similarly, it prevents the outflow of air from the first motor and fanfrom being discharged anywhere except into the second motor and fan. Anintake aperture is provide in the housing. In the preferred embodiment,the intake aperture is slightly smaller than the intake openings to thefirst fan. This will cause the air entering the housing to accelerate,thereby further strengthening the vacuum. The intake aperture to thehousing is preferably separated from the intake opening to the firstfan.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a preferred embodiment of ahousing containing a plurality of motors and fans in series.

FIG. 2 is a rear end view of a preferred embodiment of a housingcontaining a plurality of motors and fans in a series.

FIG. 3 is a cut-away side view of a preferred embodiment of a housingcontaining a plurality of motors and fans in series.

FIG. 4 is an front end view of a preferred embodiment of a fan.

FIG. 5 is a rear end view of a preferred embodiment of a motor and fan.

FIG. 6 is an exploded perspective view of a preferred embodiment of amotor and fan with cover and base plate.

FIG. 7 is a partial cut-away front end view of a preferred embodiment ofa fan mounted over a base plate.

FIG. 8 is a side view of a preferred embodiment of a vacuum containing apreferred embodiment of a housing containing a plurality of motors andfans in series.

FIG. 8A is a side view of another preferred embodiment of a vacuumcontaining another preferred embodiment of a housing containing aplurality of motors and fans in series.

FIG. 9 is an exploded perspective view of one preferred embodiment of ahousing containing a plurality of motors and fans in series.

DETAILED DESCRIPTION OF THE BEST MODE OF THE INVENTION

A vacuum 1 having a series of motors 2 is disclosed. Each motor 2 has amotor shaft 2A which drives a fan 3. Fans 3 may take any conventionalshape; however, the preferred embodiment employs a radial fanconfiguration. A radial fan 4 has an upper surface 5 and a lower surface6. Upper surface 5 contains an intake opening 7. Intake opening 7 ispreferably centrally positioned in upper surface 5. A plurality of vanes8 are positioned between upper surface 5 and lower surface 6. Vanes 8preferably extend from intake opening 7 to the outside edge 9 of fan 3.Vanes 8 are preferably curved. When fan 3 rotates, air will be drawninto intake opening 7 and pushed out of radial fan 4 at outside edge 9.

There is preferably a base plate 10 between motor 2 and fan 3. Baseplate 10 is preferably wider than fan 3. Base plate 10 is alsopreferably provided with a plurality of vents 11 between the outsideedge 9 of fan 3 and periphery of base plate 10. Vents 11 will allow airentrained by fan 3 to pass through base plate 10. Vents 11 may beprovided with fluting 12 to allow air entrained by fan 3 to pass throughbase plate 10 at an angle. This will allow air to pass through baseplate 10 with less turbulence than would be the case if air wererequired to pass through base plate 10 at a right angle thereto.

A fan cover 13 is preferably provided over fan 3. Fan cover 13 willmount to base plate 10 and will contain an intake opening 7A in linewith intake opening 7. Fan cover 13 will allow air to enter fan 3 viaintake opening 7 but will ensure that substantially all of the airexiting fan 3 will pass through vents 1 1 in base plate 10.

A plurality of motors 2 and fans 3 are preferably placed in a series 14,one in line with the other. Although in the preferred embodiment series14 only contains two motors 2 and two fans 3, it will be appreciatedthat a series 14 comprising any number of motors 2 and fans 3 may beused.

Series 14 is preferably contained within a housing 15. Housing 15 ispreferably made of plastic, metal or other suitable airtight material.One or more motors 2, fans 3, base plates 10, and fan covers 13 will bepositioned within housing 15. Housing 15 will have an inside diameterthat is coextensive with the periphery of each base plate 10. Theconnection between housing 15 and each base plate 10 will besubstantially air tight, such that air will only be able to pass fromone side of base plate 10 to the other by passing through vents 1 1.

Housing 15 will have an intake end 16 and a discharge end 17. Fans 3will be oriented in housing 15 so that intake openings 7 of fans 3 willface intake end 16 of housing 15. Discharge end 17 will include adischarge vent 31 and will preferably comprise the base plate 10 of oneof the motor 2/fan 3 combinations, such that one of the motors 2 willactually be positioned outside of housing 15. In the preferredembodiment, vents 11 in the base plate 10 at discharge end 17 will serveas discharge vent 31.

In one preferred embodiment, intake end 16 will contain an intakeaperture 18. Intake aperture 18 is preferably slightly smaller thanintake openings 7 and 7A. Intake aperture 18 is preferably separatedfrom intake opening 7 of the leading fan 3 in housing 15, mostpreferably by a distance about equal to or greater than the diameter ofbase plate 10.

In another preferred embodiment, intake end 16 of housing 15 will beformed by cover 13 and/or base plate 10 of the leading motor 2/fan 3combination as illustrated in FIGS. 8A and 9.

Housing 15 further comprises substantially airtight sidewalls 19 thatextend from intake end 16 to discharge end 17. In the preferredembodiment, sidewalls 19 will taper outward smoothly from intakeaperture 18 to where housing 15 meets base plate 10 of the leading fan 3in housing 15. In one embodiment, illustrated in FIGS. 1, 3, and 8, thevolume within housing 15 will preferably increase when viewed fromintake aperture 18 to base plate 10, herein the expanded zone 26. Inanother preferred embodiment, the volume within housing 15 will remainsubstantially constant.

Although sidewalls 19 are preferably airtight, passages may be providedin sidewalls 19 to accommodate electrical lines leading to motors 3contained within housing 15. These passages will preferably besubstantially sealed with silicone or the like in order to render themsubstantially airtight after the necessary wires are in place.

Positioning the motors 2 and fans 3 of series 14 in housing 15 willallow the power of each fan 3 exerted on the airstream to be compounded.Air flowing into the leading fan 3 in series 14 will pass through a baseplate 10 which will effectively separate one fan 3 from the next. Theair exiting the leading base plate 10 will be the only inflow airavailable to the next fan 3 in series 14. Acting together, two fans 3 inseries 14 are expected to be able to move roughly twice the amount ofair as any one of them acting alone. Similar results are expected whenadditional fans 3 are included in the series.

In the preferred embodiment, housing 15 containing series 14 ispositioned in a vacuum 1 having a body 20. Vacuum body 20 will include apower source 21 operatively connected to motors 2 in series 14 andpreferably a switch 22 for activating and deactivating the connectionbetween power source 21 and motors 2. Power source 21 may be batteries,a connection to a wall or automotive outlet, or any other conventionalpower source. Vacuum body 20 will also include a nozzle 23 configured toallow an airstream into vacuum 1. Vacuum body 20 will also include afilter 24 for separating dirt, dust, and the like from the airstreamentering vacuum 1. Housing 15 will be positioned within vacuum body 20to pull the airstream from the surroundings through nozzle 23 and intovacuum 1 so that the airstream passes through filter 24. Once the debrisin the airstream has been removed by filter 24, the airstream will passthrough housing 15 and exit vacuum 1 via an exhaust vent 25.

By placing fans 3 in series 14, additional vacuum strength is obtainedwithout increasing the girth—the external diameter—of vacuum 1. Becausemotors 2, fans 3, and especially base plates 10 are positioned invertical alignment with each other (i.e., fans 3 and base plates 10 arein substantially parallel planes and fans 3 are on substantially thesame axis), series 14 will not have any greater girth than any one motor2, fan 3, and base plate 10 alone. Thus, vacuum 1 will not have to beany wider to accommodate series 14 than it would have had to be toaccommodate a single less powerful fan 3 and motor 2.

As noted above, in one embodiment intake aperture 18 is preferablynarrower than intake opening 7. Forcing the airstream through a smalleropening should require the airstream to accelerate. Faster flow of theairstream will also increase the strength of vacuum 1. Separating intakeaperture 18 from intake opening 7 and providing the expanded zone 26between intake aperture 18 and intake openings 7, 7A should helpminimize the effect of any turbulence created in the airstream by thepassage through intake aperture 18.

Although the invention has been described in terms of its preferredembodiment, other embodiments will be apparent to those of skill in theart from a review of the foregoing. Those embodiments as well as thepreferred embodiments are intended to be encompassed by the scope andspirit of the following claims.

1. A vacuum comprising a body having a nozzle configured to allow airinto said body and an exhaust vent configured to allow air to exit saidbody; a filter configured to separate dust and debris from air passingthrough said body; a power source a housing containing a leading fan andat least one following fan, each said fan being operatively connected toand rotated by a motor in operative connection with said power source,each said fan configured to intake and discharge air, wherein saidleading fan is positioned to intake air external to said housing andwherein said following fan is positioned to intake the air dischargedfrom said leading fan, and wherein said leading fan and said followingfan are aligned with each other in said housing so that said fans rotatein substantially parallel planes and so that said fans rotate onsubstantially the same axis; and wherein said housing and said fans arepositioned in said body to draw air into said nozzle, through saidfilter, through said housing and out said exhaust vent.
 2. A vacuumaccording to claim 1 wherein at least one of said fans is a radial fan.3. A vacuum according to claim 2 wherein at least one of said fansfurther comprises a plurality of curved vanes.
 4. A vacuum according toclaim 2 wherein at least one of said fans is enclosed within a baseplate and a fan cover.
 5. A vacuum according to claim 4 wherein saidbase plate comprises a vent and wherein said fan cover comprises acentrally located intake opening, whereby the intake and discharge ofair from said at least one of said fans may be controlled.
 6. A vacuumaccording to claim 1 wherein said housing further comprises and intakeend, a discharge end, and substantially airtight sidewalls extendingtherebetween.
 7. A vacuum according to claim 6 wherein said intake endfurther comprises an intake aperture and wherein said discharge endfurther comprises a discharge vent.
 8. A vacuum according to claim 7further comprising a base plate positioned between said leading fan andsaid at least one following fan, said base plate having a vent providingair passage through said base plate and wherein said base plate and saidsidewalls are in substantially air tight engagement whereby air may notpass from said leading fan to said at least one following fan via saidhousing without passing through said vent in said base plate.
 9. Avacuum according to claim 8 wherein said leading fan is separated fromsaid intake aperture of said housing by a distance that is at leastabout the diameter of said leading fan.
 10. A vacuum according to claim8 wherein said leading fan is provided with a fan cover having acentrally positioned intake opening, said cover and intake openingpositioned and configured to substantially prevent the intake of air bysaid leading fan except through said intake opening.
 11. A vacuumaccording to claim 10 wherein said intake opening of said cover isseparated from said intake aperture of said housing by a distance thatis at least about the diameter of said leading fan.
 12. A vacuumaccording to claim 11 wherein said intake aperture of said housing issmaller in area than said intake opening of said cover.
 13. A vacuumaccording to claim 12 wherein said sidewalls taper outward from saidintake aperture to where said sidewalls meet said base plate.
 14. Avacuum according to claim 11 wherein said sidewalls taper outward fromsaid intake aperture to where said sidewalls meet said base plate.